Please wait a moment until the data is sorted. This message will disappear when the data is sorted.

SYSTEMATIC NAME

IUBMB Comments

cyanophycin:L-aspartate ligase (ADP-forming)

Requires Mg2+ for activity. Both this enzyme and EC 6.3.2.30, cyanophycin synthase (L-arginine-adding), are required for the elongation of cyanophycin, which is a protein-like cell inclusion that is unique to cyanobacteria and acts as a temporary nitrogen store [2]. Both enzymes are found in the same protein but have different active sites [2,4]. Both L-Asp and L-Arg must be present before either enzyme will display significant activity [2].

heterocysts conspicuously accumulate polar granules made of cyanophycin, which is synthesized by cyanophycin synthetase. Heterocysts provide the vegetative cells with fixed nitrogen. The nitrogen-rich molecule beta-aspartyl-arginine is a nitrogen vehicle in the unique multicellular system represented by the heterocyst-forming cyanobacteria. Production of the dipeptide by isolated heterocysts is essentially dependent on cyanophycin

in comparison to parent strain SM101, the spores of a CphA mutant strain retain wild-type levels of heat resistance, but fewer spores are made, and they are smaller, suggesting that cyanophycin synthesis plays a role in spore assembly

expression in commercial Nicotiana tabacum cultivars Badischer Geudertheimer (BG) and Virginia Golta (VG). Both in F1 hybrids (max. 9.4% CP/DW) and T0 transformants (max. 8.8% CP/DW), a substantial increase in cyanophycin content is achieved in leaf tissue. In BG, cyanophycin yields are homogenous and there is no substantial difference in the variation of the cyanophycin content between primary transformants (T0), clones of T0 individuals, T1 siblings and F1 siblings of hybrids

heterocysts conspicuously accumulate polar granules made of cyanophycin, which is synthesized by cyanophycin synthetase. Heterocysts provide the vegetative cells with fixed nitrogen. The nitrogen-rich molecule beta-aspartyl-arginine is a nitrogen vehicle in the unique multicellular system represented by the heterocyst-forming cyanobacteria. Production of the dipeptide by isolated heterocysts is essentially dependent on cyanophycin

in comparison to parent strain SM101, the spores of a CphA mutant strain retain wild-type levels of heat resistance, but fewer spores are made, and they are smaller, suggesting that cyanophycin synthesis plays a role in spore assembly

[L-Asp(4-L-Arg)]n-Asp is a cyanophycin molecule with a C-terminal L-Asp residue that is not linked to an L-Arg residue via its beta-carboxy group, this intermediate is produced in the first reaction catalysed by cyanophycin synthase

[L-Asp(4-L-Arg)]n-Asp is a cyanophycin molecule with a C-terminal L-Asp residue that is not linked to an L-Arg residue via its beta-carboxy group, this intermediate is produced in the first reaction catalysed by cyanophycin synthase

[L-Asp(4-L-Arg)]n-Asp is a cyanophycin molecule with a C-terminal L-Asp residue that is not linked to an L-Arg residue via its beta-carboxy group, this intermediate is produced in the first reaction catalysed by cyanophycin synthase

without L-arginine 1.1% activity compared to the reaction mixture containing both substrates, no activity using L-lysine instead of L-arginine, no activity without addition of small amounts of cyanophycin as a primer for synthesis

cyanophycin synthetase catalyzes the synthesis of cyanophycin by ATP-dependent polymerization of L-Asp and L-Arg. In vitro, the activity of CphA generally depends on the presence of L-Asp, L-Arg, ATP, Mg2+, K+, sulfhydryl compound, and cyanophycin as primers

the recombinant CphA49 exhibits strict primer dependency and broad substrate specificities. L-Lys and L-Glu can substitute for L-Asp, but with very low catalytic activity. No activity with L-Arg and L-citrulline, L-Arg and L-ornithine, L-Asp and L-citrulline, and L-Asp and L-ornithine

without L-arginine 1.1% activity compared to the reaction mixture containing both substrates, no activity using L-lysine instead of L-arginine, no activity without addition of small amounts of cyanophycin as a primer for synthesis

cyanophycin synthetase catalyzes the synthesis of cyanophycin by ATP-dependent polymerization of L-Asp and L-Arg. In vitro, the activity of CphA generally depends on the presence of L-Asp, L-Arg, ATP, Mg2+, K+, sulfhydryl compound, and cyanophycin as primers

Please wait a moment until the data is sorted. This message will disappear when the data is sorted.

STORAGE STABILITY

ORGANISM

UNIPROT

LITERATURE

at 7°C the purified enzyme is stable for about one week, thereafter the activity decreases rapidly, storage at -20°C in the presence of 10% (w/v) DMSO or 50% (w/v) glycerol does not improve the stability significantly

functional expression in Nicotiana tabacum var. Petit Havana SRI targeted to the chloroplasts using the CaMV 35S promoter and a translocation pathway signal sequence, the phenotypic abnormalities are reduced by this way, cyanophycin accumulation in chloroplasts, overview

gene cphA6308, functional expression in Saccharomyces cerevisiae strains G175 and BY4741, which is much more efficient with the copper ion-inducible CUP1 promoter instead of the GAL1 promoter, the yeast strains produce water-soluble and water-insoluble cyanophycin polymer. Growth of transgenic yeasts in the presence of 15 mM lysine results in an incorporation of up to 10 mol% of lysine into cyanophycin, overview. Subcloning in Escherichia coli strain XL1-Blue

two truncated CphAs, lacking 31 (CphANE1del96) or 59 (CphANE1del180) amino acids of the C-terminal region, are derived from cphANE1 by deleting 96 or 180 bp from its 3' region through the introduction of stop codons. In comparison to the wild-type gene, cphANE1del96 conferrs about 2.1-2.2fold higher enzyme activity on Escherichia coli. These cells accumulate about twofold more cyanophycin than cells expressing the wild-type gene

construction of truncation mutant CphANE1?C45, which lacks up to 45 amino acids at its C-terminus, the mutant retains full enzymatic activity and produced polymers, however, the removal of one additional amino acid, Glu856, results in complete inactivation of CphANE1?C46, phenotype, overview. Removal of the sequence Leu867-Leu870 results in dramatically decreased thermostability

construction of truncation mutant CphANE1?C45, which lacks up to 45 amino acids at its C-terminus, the mutant retains full enzymatic activity and produced polymers, however, the removal of one additional amino acid, Glu856, results in complete inactivation of CphANE1?C46, phenotype, overview. Removal of the sequence Leu867-Leu870 results in dramatically decreased thermostability

restriction of cyanophycin accumulation to the potato tubers by using the cyanophycin synthetase gene from Thermosynechococcus elongatus BP-1, under the control of the tuber-specific class 1 promoter. Tuber-specific cytosolic expression by pB33-cphATe as well as tuber-specific plastidic expression by pB33-PsbYcphATe results in significant polymer accumulation solely in the tubers. In plants transformed with pB33-cphATe, both cyanophycin synthetase and cyanophycin are detected in the cytoplasm leading to an increase up to 2.3% cyanophycin of dry weight and resulting in small and deformed tubers. In B33-PsbY-cphATe tubers, cyanophycin synthetase and cyanophycin are exclusively found in amyloplasts leading to a cyanophycin accumulation up to 7.5% of dry weight. These tubers are normal in size, some clones show reduced tuber yield and sometimes exhibit brown sunken staining starting at tubers navel. During a storage period over of 32 weeks of one selected clone, the cyanophycin content was stable in B33-PsbYcphATe tubers but the stress symptoms increased. Nitrogen fertilization in the greenhouse does not lead not to an increased cyanophycin yield, slightly reduced protein content, decreased starch content, and changes in the amounts of bound and free arginine and aspartate

expression of cyanophycin synthase in wild-type Sinorhizobium meliloti 1021 and in a phbC-negative mutant. Yeast mannitol broth yields the highest cyanophycin contents in both Sinorhizobium meliloti 1021 strains. Supplying the medium with isopropyl-beta-D-thiogalactopyranoside, aspartic acid, and arginine enhances cyanophycin contents about 2.5- and 2.8fold. Varying the nitrogen-to-carbon ratio in the medium enhanced the cyanophycin content further to 43.8% w/w of cell dry weight. Cyanophycin from the Sinorhizobium meliloti strains consists of equimolar amounts of aspartic acid and arginine and contains no other amino acids even if the medium is supplemented with glutamic acid, citrulline, ornithine, or lysine. Cyanophycin isolated from Sinorhizobium meliloti exhibits average molecular weights between 20 and 25 kDa. Cyanophycin isolated after expression in Escherichia coli S17-1 exhibits average molecular weight between 22 and 30 kDa. Co-expression of cyanophycinase from Anabaena sp. PCC7120 encoded by cphB17120 in cphA17120-positive Escherichia coli S17-1, Sinorhizobium meliloti 1021, and its phbC-negative mutant gives cyanophycinase activities in crude extracts, and no CGP granules occur

synthesis of cyanophycin using an anabolism-based media-dependent plasmid addiction system to enhance plasmid stability, and a process based on a modified mineral salts medium yielding a cyanophycin content of 42% w/w at the maximum without the addition of amino acids to the medium. This plasmid addiction system is based on different lysine biosynthesis pathways and consists of a knockout of the chromosomal dapE that disrupts the native succinylase pathway in Escherichia coli and the complementation by the plasmid-encoded artificial aminotransferase pathway mediated by the dapL gene from Synechocystis sp. PCC 6308, which allows the synthesis of the essential lysine precursor L,L-2,6-diaminopimelate. This plasmid also harbors an engineered cyanophycin synthetase gene responsible for cyanophycin production. Cultivation experiments reveal an at least 4.5fold enhanced production of cyanophycin in comparison to control cultivations

expression of the cyanophycin synthetase of Synechocystis sp. PCC 6308 in Pseudomonas putida ATCC 4359 using an optimised medium for cultivation, results in synthesis of insoluble cyanophycin up to 14.7 w/w and soluble cyanophycin amounting up to 28.7 w/w of the cell dry matter. The soluble CGP is composed of 50.4 mol% aspartic acid, 32.7 mol% arginine, 8.7 mol% citrulline and 8.3 mol% lysine. The insoluble cyanophycin contains less than 1 mol% of citrulline. Using a mineral salt medium with 1.25 or 2% w/v sodium succinate, respectively, plus 23.7 mM L-arginine, the cells synthesise insoluble cyanophycin amounting up to 25% to 29% of the CDM with only a very low citrulline content

cyanophycin produced in Escherichia coli is composed of 50% of aspartic acid, 45% of arginine, and 3.5% of lysine, and exhibits a homogenous molecular mass of 35 kDa. Cultivation in presence of arginine, aspartic acid, lysine and glucose with the minimal resource leads to 1.72 g/l soluble cyanophycin

expression of cyanophycin synthase in wild-type Sinorhizobium meliloti 1021 and in a phbC-negative mutant. Yeast mannitol broth yields the highest cyanophycin contents in both Sinorhizobium meliloti 1021 strains. Supplying the medium with isopropyl-beta-D-thiogalactopyranoside, aspartic acid, and arginine enhances cyanophycin contents about 2.5- and 2.8fold. Varying the nitrogen-to-carbon ratio in the medium enhanced the cyanophycin content further to 43.8% w/w of cell dry weight. Cyanophycin from the Sinorhizobium meliloti strains consists of equimolar amounts of aspartic acid and arginine and contains no other amino acids even if the medium is supplemented with glutamic acid, citrulline, ornithine, or lysine. Cyanophycin isolated from Sinorhizobium meliloti exhibits average molecular weights between 20 and 25 kDa. Cyanophycin isolated after expression in Escherichia coli S17-1 exhibits average molecular weight between 22 and 30 kDa. Co-expression of cyanophycinase from Anabaena sp. PCC7120 encoded by cphB17120 in cphA17120-positive Escherichia coli S17-1, Sinorhizobium meliloti 1021, and its phbC-negative mutant gives cyanophycinase activities in crude extracts, and no CGP granules occur

expression of the cyanophycin synthetase of Synechocystis sp. PCC 6308 in Pseudomonas putida ATCC 4359 using an optimised medium for cultivation, results in synthesis of insoluble cyanophycin up to 14.7 w/w and soluble cyanophycin amounting up to 28.7 w/w of the cell dry matter. The soluble CGP is composed of 50.4 mol% aspartic acid, 32.7 mol% arginine, 8.7 mol% citrulline and 8.3 mol% lysine. The insoluble cyanophycin contains less than 1 mol% of citrulline. Using a mineral salt medium with 1.25 or 2% w/v sodium succinate, respectively, plus 23.7 mM L-arginine, the cells synthesise insoluble cyanophycin amounting up to 25% to 29% of the CDM with only a very low citrulline content; synthesis of cyanophycin using an anabolism-based media-dependent plasmid addiction system to enhance plasmid stability, and a process based on a modified mineral salts medium yielding a cyanophycin content of 42% w/w at the maximum without the addition of amino acids to the medium. This plasmid addiction system is based on different lysine biosynthesis pathways and consists of a knockout of the chromosomal dapE that disrupts the native succinylase pathway in Escherichia coli and the complementation by the plasmid-encoded artificial aminotransferase pathway mediated by the dapL gene from Synechocystis sp. PCC 6308, which allows the synthesis of the essential lysine precursor L,L-2,6-diaminopimelate. This plasmid also harbors an engineered cyanophycin synthetase gene responsible for cyanophycin production. Cultivation experiments reveal an at least 4.5fold enhanced production of cyanophycin in comparison to control cultivations

Partial purification and characterization of a non-cyanobacterial cyanophycin synthetase from Acinetobacter calcoaceticus strain ADP1 with regard to substrate specificity, substrate affinity and binding to cyanophycin